• The Korean Journal of Food And Nutrition
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• v.14 no.5
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• pp.385-390
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• 2001

The enzyme activity and organoleptic properties of Korean pickled cucumber were studies for their changes during fermentation. The Korean pickled cucumber were prepared by blanching and high temperature soaking in salt solution and trehalose treament. The results showed that the effect of combined heat and trehalose treatment significantly reduced the fermentation rate and softening rate of texture while a rather rapid fermentation was for those preserved with salt. The effect of terhalose treatment enhanced fermentation and it was significantly reduced softening rate of texture by 2% treatment. The sensory evaluation of Korean pickled cucumber was found that combined heat treatment with blanching and hot solution had a positive effect for reduction of softening of cucumber tissue, however, odor and taste were not significantly affected. This study suggested that combined heat and trehalose treament might have potential for affording protection against softness of cucumber tissue during the fermentation time.

• KSBB Journal
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• v.22 no.2
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• pp.84-90
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• 2007

Trehalose is non-reducing disaccharide which is found in bacteria, fungi, plants and insects. Trehalose has been determined by several analysis methods. To monitor the concentrations of trehalose in a process, enzymatic methods have more advantage over others, e.g. more specific. In this work, trehalase was immobilized on VA-epoxy polymer and applied to FIA systems. The behaviours of these FIA systems were characterized and used to monitor the trehalose concentrations. Use of optical detection technique was chosen for trehalose-FIA system. On-line monitoring data and off-line data were measured by HPLC.

• Journal of Veterinary Clinics
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• v.34 no.2
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• pp.156-160
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• 2017

We investigated the effect of ethylene glycol and antioxidants such as taurine, hypotaurine and trehalose with extenders during cryopreservation of Korean Jeju Black Bull spermatozoa. The cryopreservation of freshly collected spermatozoa was conducted with four different conditions. As a control, spermatozoa were cryopreserved with Tris egg-yolk extenders added 5% ethylene glycol (EG). Taurine (20 mM), hypotaurine (20 mM) and trehalose (20 mM) were individually added into tris egg-yolk extenders with 5% EG. After thawing of frozen spermatozoa with four different conditions, sperm viability, motility, acrosomal integrity, and membrane integrity were investigated. The significant (p < 0.05) improvement of sperm viability showed in all antioxidant treated thawed spermatozoa (taurine; $68.1%{\pm}4.4$, hypotaurine; $69.2%{\pm}6.7$ and trehalose; $68.0%{\pm}4.4$) when compared to control ($63.4%{\pm}5.6$). Neither positive nor detrimental effects of three antioxidants were shown sperm motility after thawing. The results of hypo-osmotic swelling test showed that the membrane integrity of taurine, hypotaurine or trehalose treated thawed spermatozoa ($64.1%{\pm}5.4$, $61.5%{\pm}3.7$ and $59.0%{\pm}4.0$, respectively) had significantly (p < 0.05) higher rate of the swollen sperm compared to control ($53.7%{\pm}9.7$). Hypotaurine treated frozen-thawed spermatozoa had siginificantly higher (p < 0.05) F pattern ratio than taurine, trehalose and control treated frozen-thawed spermatozoa. Trehalose added frozen-thawed spermatozoa had significantly higher (p < 0.05) acrosome reaction pattern ratio than taurine and hypotaurine added frozen-thawd spermatozoa. In this study, we found that antioxidants such taurine, hypotaurine and trehalose treatments during cryopreservation process could reduce damage of spermatozoa of Korean Jeju Black Bull and improved sperm capability of fertilization.

• Korean Journal of Food Science and Technology
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• v.42 no.3
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• pp.304-309
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• 2010

Instant Baekseolgi containing 0, 1, 2, and 3% trehalose prepared using a microwave oven, after which quality characteristics were investigated over 24 hr. The sample was prepared to internal and external parts. The moisture content of Baekseolgi without trehalose (control) was not reduced. However, the presence of trehalose reduced moisture content of two different groups (p<0.05). Weight reduction of Baekseolgi was decreased with increased threhalose content (p<0.05). The hardness, and chewiness of Baekseolgi with trehalose was decreased with increased trehalose (p<0.05). However adhesiveness, springiness, and cohesiveness were not significantly changed. The results of sensory evaluation showed that moisture and hardness were reduced between the internal and external parts of the Baekseolgi with increased trehalose (p<0.05). This study shows that the addition of trehalose to Baekseolgi had a positive impact on quality characteristics, including moisture content, weight reduction, texture, and sensory properites.

• Korean journal of food and cookery science
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• v.24 no.6
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• pp.912-918
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• 2008

This study was conducted to evaluate the quality characteristics of Backsulgies prepared using different ratios (0, 10, 20, 30, 40%) of trehalose after 4 days of storage. As the concentration of trehalose increased, the moisture content of the Backsulgies decreased. Furthermore, increased levels of trehalose, resulted in significantly lower L and b values. However, the a values did not differ significantly in response to the addition of trehalose. The total cell counts of Backsulgies also decreased as the level of trehalose increased, which indicates that microorganisms were inhibited by its addition. Furthermore, the hardness of the Backsulgies decreased as the level of trehalose increased, whereas the hardness of the Backsulgies increased as the storage time was extended. Finally, the sensory evaluations revealed that the chewiness and hardness of Backsulgies decreased as the level of trehalose increased.

• Culinary science and hospitality research
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• v.20 no.3
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• pp.113-124
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• 2014

This study investigated the quality characteristics of Yanggeng sweetened with various amounts of trehalose (0, 40, 60, 80, 100 % of trehalose) and their changes during storage times. The moisture content, color value, $^{\circ}Brix$, pH, texture profile, QDA and acceptance for samples were tested. As a result of the mechanical tests, moisture content and pH were increased while hardness were decreased with increased trehalose content. Also, moistness, gloss and after taste were increased with increased trehalose in the sensory attribute difference test. Acceptance test showed Yanggeng with 60% trehalose and 40% sucrose obtained the highest scores on flavor, taste and overall acceptability. During storage in refrigerator, Yanggeng sweetened with higher % of trehalose showed significantly higher moisture content, and lower syneresis and hardness than the control sweetened with only sucrose. The results of the sensory test showed that 60% trehalose Yanggeng was the highest in flavor, after taste, and overall acceptability.

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1544-1549
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• 2008

MhMTS and MhMTH are trehalose ($\alpha$-D-glucopyranosyl-[1,1]-$\alpha$-D-glucopyranose) biosynthesis genes of the thermophilic microorganism Metallosphaera hakonensis, and encode a maltooligosyltrehalose synthase (MhMTS) and a maltooligosyltrehalose trehalohydrolase (MhMTH), respectively. In this study, the two genes were fused in-frame in a recombinant DNA, and expressed in Escherichia coli to produce a bifunctional fusion enzyme, MhMTSH. Similar to the two-step reactions with MhMTS and MhMTH, the fusion enzyme catalyzed the sequential reactions on maltopentaose, maltotriosyltrehalose formation, and following hydrolysis, producing trehalose and maltotriose. Optimum conditions for the fusion enzyme-catalyzed trehalose synthesis were around $70^{\circ}C$ and pH 5.0-6.0. The MhMTSH fusion enzyme exhibited a high degree of thermostability, retaining 80% of the activity when pre-incubated at $70^{\circ}C$ for 48 h. The stability was gradually abolished by incubating the fusion enzyme at above $80^{\circ}C$. The MhMTSH fusion enzyme was active on various sizes of maltooligosaccharides, extending its substrate specificity to soluble starch, the most abundant natural source of trehalose production.

• Journal of Microbiology and Biotechnology
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• v.17 no.10
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• pp.1675-1681
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• 2007

The pseudodisaccharide salbostatin, which consists of valienamine linked to 2-amino-1,5-anhydro-2-deoxyglucitol, is a strong trehalase inhibitor. From our Streptomyces albus ATCC 21838 genomic library, we identified thirty-two ORFs in a 37-kb gene cluster. Twenty-one genes are supposed to be a complete set of modules responsible for the salbostatin biosynthesis. Through sequence analysis of the gene cluster, some of the upstream gene products (SalB, SalC, SalD, SalE, and SalF) revealed functional resemblance with trehalose biosynthetic enzymes. On the basis of this rationale, we isolated the five genes (salB, salC, salD, salE, and salF) from the S. albus ATCC 21838 and cloned them into the expression vector pWHM3. We demonstrated the noticeable expression and accumulation of trehalose, using only the five upstream biosynthetic gene cluster of salbostatin, in the transformed Streptomyces lividans TK24. Finally, 490 mg/l trehalose was produced by fermentation of the transformant with sucrosedepleted R2YE media.

• Korean Journal of Microbiology
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• v.8 no.2
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• pp.85-89
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• 1970

Effects of the sugar content in molasses media and pH on cell constituents of produced yeast adopting Saccharomyces cerevisiae Rasse O as a seed organism were studied, and following results were obtained. 1. Trehalose accumulation of the yeast was reduced at lower range of pH, however protein was increased. 2. Trehalose content of the yeast enriched by feeding increased sugar at suitable pH. 3. There was no significant increase of thehalose content in the cell by feeding concentrated molasses at lower range of pH.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.199-202
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• 2008

The effects of $\beta$-(1,6)-galactosyl trehalose trisaccharide ($\beta$-GT) that was preferentially produced by Escherichia coli $\beta$-galactosidase on cryo- and thermo-protections of protein were investigated with those of other sugars at the level of 8% (w/v). As compared to a control without sugar additive, $\beta$-GT effectively enhanced 32-54% of the cryoprotection of fish actomyosin against repeated freeze-thawing and frozen storage, and also 49% of the protection against thermal inactivation of pyrophosphatase, respectively. As a result, it was significantly more effective than sorbitol and trehalose in both cryoprotection and thermoprotection. Thus, $\beta$-GT would be possibly applied as a sugar substitute for cryo- and thermo-protective applications of food protein.